name: CI

on:
  push:
    branches: [main]
  pull_request:
    types: [opened, synchronize, reopened, labeled]

permissions:
  contents: write
  pull-requests: write

jobs:
  vet_build_test:
    name: Vet & Build & Test
    runs-on: ${{ matrix.os }}
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-latest, windows-latest]
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-go@v5
        with:
          go-version-file: go.mod

      - name: Find and remove all .cpp files
        run: |
          find . -name "*.cpp" -type f -delete
        shell: bash

      - name: Run go vet
        run: go vet ./...

      - name: Build all packages
        run: go build ./...

      - name: Build cmd/gen
        run: go build ./cmd/gen

      - name: Run tests
        run: go test -v -count=1 ./...


  test-examples:
    name: Test examples (${{ matrix.name }})
    runs-on: ${{ matrix.os }}
    needs: [vet_build_test]
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-latest
            name: Linux
            cmake_extra_args: -DCMAKE_INSTALL_PREFIX=/usr/local
            install_cmd: >-
              sudo cmake --install level-zero-build &&
              sudo cp level-zero-build/lib/libze_null.so /usr/local/lib/ &&
              sudo ldconfig
          - os: windows-latest
            name: Windows
            cmake_extra_args: ""
            install_cmd: >-
              for dll in $(find level-zero-build -name "*.dll");
                do cp "$dll" /c/Windows/System32/;
              done
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-go@v5
        with:
          go-version-file: go.mod

      - name: Download Intel Level Zero Source Code
        shell: bash
        run: |
          # The apt runtime package (libze1) does NOT ship libze_null, which is
          # required for ZE_ENABLE_NULL_DRIVER=1. Build from source instead so the
          # loader and the null driver are both present
          RELEASE=$(curl -sf https://api.github.com/repos/oneapi-src/level-zero/releases/latest \
            | jq -r '.tag_name')
          git clone https://github.com/oneapi-src/level-zero.git --depth=1 \
            --branch "$RELEASE" level-zero-src

      - name: Build & Install Intel Level Zero
        shell: bash
        run: |
          cmake -S level-zero-src -B level-zero-build \
            -DCMAKE_BUILD_TYPE=Release \
            -DBUILD_TESTING=OFF \
            ${{ matrix.cmake_extra_args }}
          cmake --build level-zero-build --config Release --parallel $(nproc)
          ${{ matrix.install_cmd }}

      - name: Run examples
        shell: bash
        env:
          # Activate the Level Zero null driver (ze_null) so the loader
          # can enumerate a fake device on runners without real Intel GPU hardware.
          ZE_ENABLE_NULL_DRIVER: "1"
        run: |
          for dir in examples/*/; do
            if [ -f "${dir}/main.go" ]; then
              echo "==> Running ${dir}..."
              go run "./${dir}/main.go"
            fi
          done

  go-generate:
    name: Run all Generates & Commit
    runs-on: ubuntu-latest
    needs: [vet_build_test]
    steps:
      - uses: actions/checkout@v4
        with:
          ref: ${{ github.head_ref || github.ref_name }}
          token: ${{ secrets.GITHUB_TOKEN }}

      - uses: actions/setup-go@v5
        with:
          go-version-file: go.mod

      - name: Download SYCL Linux
        run: |
          wget -q -O /tmp/sycl_linux.tar.gz https://github.com/intel/llvm/releases/download/v6.3.0/sycl_linux.tar.gz
          mkdir -p /tmp/sycl_linux
          tar -xzf /tmp/sycl_linux.tar.gz -C /tmp/sycl_linux

      - name: Add SYCL bin to PATH
        run: |
          ls -hl /tmp/sycl_linux
          echo "/tmp/sycl_linux/bin" >> $GITHUB_PATH

      - name: Install ocloc
        run: |
          wget -qO- https://repositories.intel.com/gpu/intel-graphics.key \
            | sudo gpg --dearmor --output /usr/share/keyrings/intel-graphics.gpg
          echo "deb [arch=amd64 signed-by=/usr/share/keyrings/intel-graphics.gpg] https://repositories.intel.com/gpu/ubuntu $(. /etc/os-release && echo $VERSION_CODENAME) unified" \
            | sudo tee /etc/apt/sources.list.d/intel-gpu.list
          sudo apt-get update -q
          sudo apt-get install -y intel-ocloc libigdfcl2 libigc2

      - name: Run go generate
        run: |
          go generate ./...
          gofmt -w .

      - name: Run golangci-lint
        uses: golangci/golangci-lint-action@v9
        with:
          version: v2.11
          args: --fix
        env:
          CGO_ENABLED: "0"

      - name: Check for changes
        id: diff
        run: |
          if [ -n "$(git diff --name-only)" ]; then
            echo "changed=true" >> "$GITHUB_OUTPUT"
          fi

      - name: Commit and push to PR branch
        if: steps.diff.outputs.changed == 'true' && github.event_name == 'pull_request'
        id: push_to_pr
        continue-on-error: true
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git add -A
          git commit -m "chore: run go generate"
          git push

      - name: Comment on PR if push failed
        if: steps.diff.outputs.changed == 'true' && github.event_name == 'pull_request' && steps.push_to_pr.outcome == 'failure'
        uses: actions/github-script@v7
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: '`go generate` produced file changes but could not be pushed automatically (likely a fork PR). Please run `go generate ./... && gofmt -w .` locally and push the changes.'
            })

      - name: Create Pull Request
        if: steps.diff.outputs.changed == 'true' && github.event_name == 'push'
        uses: peter-evans/create-pull-request@v7
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          commit-message: "chore: run go generate"
          title: "chore: run go generate"
          body: |
            Automated PR created by CI.

            `go generate .` detected generated file differences and applied updates.
          branch: auto/go-generate
          delete-branch: true